Vapor generator



June 9, 1953 H. H. HEMENWAY ElAL 2,641,233

VAPOR GENERATOR Filed Feb. 19, 1947 .4 Sheets-Sheet l owp * INVENTORS HENRY h. fiE/VE/VWA Y JOHN F THU/VSTAOM My ATTORNEY June 9, 1953 Filed Feb. 19, 1947 H. H. HEMENWAY ETAL 2,541,233

VAPOR GENERATOR 4 Sheets-Sheet 2 BY I ATTORNEY June 9, 1953 H. H. HEMENWAY ETAL 4 Sheets-Sheet I l l lalll l INVE TORS HENRY hf flfglz-wwn Y Patented June 9, 1953 VAPOR GENERATOR Henry H. Iiemenway, St. Albans, and John F. Thunstrom, Bronx, N. Y., assignors to Foster Wheeler Corporation, New York, N. Y., a corporation of New York Application February 19, 1947, Serial No. 729,630

This invention relates to vapor generators.

The present invention provides a vapor generator having furnaces each with a combustion chamber provided with air. under pressure for combustion so that the size of the combustion chambers and the amount of heating surface required for a given capacity. may be reducedbecause of the increased density of the air and combustion gases.

The invention also provides a vapor generator in which the air under pressure for combustion in a combustion chamber of the generator is provided through power obtained by utilizing thermal energy of the gases of combustion from said chamber.

The present invention further provides a vapor generator in which the parts thereof are so constructed and arranged that a minimum amount of heating surface is required for a given vapor generating capacity.

The invention also provides a vapor generator in which air for combustion is supplied under pressure and in which vapor temperature control is obtained by varying the relative amount of combustion gas flow over vapor generating and superheated vapor generating means.

The present invention further provides baflle means which includes vapor generating tubes of the vapor generator.

The invention will be apparent from the following description when considered in connec tion with the accompanyingdrawings forming a part thereof and in which:

Fig. l is a diagrammatic view of the arrangement of apparatus associated with the vapor generator of the present invention;

Fig. 2 is a transverse sectionalview of the vapor generator of the present invention taken on the line 22 of Fig. 3;

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2;

Fig. 4 is a longitudinal sectional view taken on the line 4--4 of Fig. 2; and

Fig. 5 is an enlarged fragmentary view taken on the line 5-5 of Fig. 2.

Like characters of reference refer to the same parts throughout the views.

Referring to the drawings, the vapor generator of the present invention comprises a cylindrica1ly-shaped setting it mounted on a base B and disposed so that the longitudinal axis thereof extends substantially horizontally. As shown in Fig. 1, the vapor generator receives air through an air inlet conduit H from an air compressor I2, driven during normal opera- 12 Claims. (Cl. 122- -240 I tion of the vapor generator by a gas turbine l3. Gas turbine I3 is actuated by gases of combustion from the vapor generator, the gases entering the turbine through gas conduit l4 communicating with the vapor generator through gas outlet conduit l5 controlled by damper l6 and through gas outlet conduit l1 controlled by damper l8. Exhaust gases from the turbine I 3 pass through conduit l9 into an economizer 2!! wherein said gases pass in heat exchange relationship with tubes 2| through which feed water for the vapor generator flows. After passing in heat exchange relationship with the tubes 2!, the gases flow into the flue 22 and thence to a stack, not shown. During the starting up of the vapor generator, the air compressor I2 is driven by an auxiliary steam turbine 23 or an electric motor.

Setting 10, as shown more particularly in Figs. 2 to 4, comprises a cylindrical metallic casing 24 formed of sections 24 and. covered on the outside thereof by a covering of insulation 25. Cylindrical casing 24 is closed at opposite ends thereof by dished heads 26 and 21, respectively, secured to said casing. The heads also comprise an inner metallic housing 28 covered on the outside thereof by an insulating covering 29.

A steam and water drum 30 is positioned within the cylindrical casing 24 at the upper part thereof and extends longitudinally of said casing. Combustion chambers 3| and 32 are provided Within the casing 24 and have an outer wall 33 of insulating material extending substantially parallel throughout the greater portion of its length to and in spaced relationship with the casing 24 thereby forming an air space 45 between casing 24 and wall 33. Wall 33 is formed in sections corresponding to sections 24' of the casing, the sections of the wall being lined on the inner surface with a metal lining 33' and on the outer surface with a metal lining 33". The linings 33 and 33" are flanged atopposite longitudinal sides thereof at 86, the flanges being discontinuous longitudinally thereof so that air may flow through passage 45, the flanges projecting across the space 45 and between adjacent longitudinal side edges of adjacent sections 24' of the casing where they are secured by welding or otherwise. In this manner, the wall 33 is supported within the casing. Wall extends from a point closely adjacent one side of the drum 3!! approximately centrally of the upper and lower extremities of said drum to a similar point on the opposite side of the drum. The space between the end of the refractory wall and the outer periphery of the drum is sealed by plates 34 (Fig. 2). Lower drums 35 and 36 extend longitudinally of the casing 24 in the lower portion thereof and are supported therein by supports 81. The drums are spaced apart and positioned on opposite sides of a vertical plane extending through the longitudinal axis of the setting and drum 3D. The drum 35 is in communication with the steam and water drum through downcomers 3'! and 38, the downcomers 31 being connected at opposite ends thereof to one end of the drum and to the corresponding end of drum 30 while the downcomer 33 is in communication at opposite ends thereof with the opposite end of the drum 335 and the corresponding end of the drum 36. Lower drum 35, like drum 35, is in communication at opposite ends thereof with the drum 3i! through the downcomer 39 and through downcomer 40.

The combustion chambers 35 and 32 are closed at "the rearward end thereof by an end well ll of insulating material extending transversely of the casing 2 between the inner periphery of wall r $3 on one side thereof and the inner periphery of said wall on the opposite side thereof and extending substantially vertically in said casing between the inner periphery of wall 33 at the top thereof and the inner periphery of said wall at the bottom. The wall 4! has a metallic lining 52 on the side thereof outwardly of the combustion chambers which lining t2 extends transversely of the setting from the inner periphery of casing 2:3 at

one side thereof to the inner periphery of said casing at the opposite side and also extends substantially vertically in the setting from the inner periphery of casing 24 at the bottom thereof to a point short of the inner periphery of the casing at the top thereof. casing 24, the chambers 3i and 32 are closed by a front wall 43 similar to rear wall 4! which also is lined on the side thereof outwardly of the combustion chamber by a metallic lining M similar to metallic lining 42. Tie pates 9t extend between A the inner periphery of the head 25 and lining 42 while tie plates 3i extend between the inner periphery of head 2? and lining Ml.

An air chamber 45 is formed between the outer wall 33 of the combustion chambers and the cas spaces 45, id and 3'? to thereby cool the casing and v the dished heads and heat said air.

Combustion chamber 31 is fired by burners 49 each enclosed by a housin 5i? while combustion chamber 32 is fired by burners each of which is enclosed in a housing 52. burner openings 53 therein each of which con municates with a burner 49 and is in communication with the chamber while each burner opening 5st through wall 43 communicates with a burner 5i and with chamber 32. Burner housings-55] and 52 extend into air chamber ll in head 2i, and are mounted therein. The housin Fill has a plurality of dampers 5'! '(Fig. 3) in opposite sides thereof by means of which the flow of air from the space 4'! to the burners is con- At the opposite end or" the i Front wall 43 has plurality of water wall tubes 33 which tubes 4 trolled. Similarly, the burner housing 52 ha dampers which controls the flow of air from the space M to the burners. Burners i receive fuel through fuel inlet conduits Bi while burners 5| receive fuel through conduits 52.

The outer wall 33 adjacent the combustion chamber 3! is lined along its i ner periphery b connected at one end thereof: with the lower portion of the drum 3% at one side of the drum and at the opposite ends thereof with the lower drum while the wall bustion chamber is lined along its iphery by plurality of water wail tubes 6 which tubes are connected at one end to the lower portion of the drum 30 on the side thereof opposite that to which the tubes 63 are connected. The opposite end of the tubes M are connected to the lower drum A substantially generally vertically extending bank 65 of spaced vapor generating tubes communicates at one end thereof with the lower portion of drum 3G and with the lower drum at the opposite end, while a similar bank of generally vertical extendine spaced tubes communicates with the lower portion of the drum 3?) and the lower drum 35.

A bottom :2 of insulathas material extends transversely of the chamber 3i above drum 35 and between water well tubes 63 and bank 65 and longitudinally of said chamber between end wall 3i and front wall 43 while a similar bottom 72 extends transversely of chamber 32 above drum 38 and between water wall tubes 54 and bank 66. Bottom 72', like bottom l2, also extends longitudinally between Walls ii and 63. Bank and bank at are spaced apart to form a central vertically extending passage 5?. As shown more particularly in Fig. 5, bank L35 of tubes comprises an inner row of spaced. tubes 63 positioned in heat exchange relationship with the gases of combustion in the chamber iii and a second row of spaced tubes adjacent the E8 and arranged so that the tubes 6i? are in aligrh ment with the spaces between the tubes 68. Adiacent tubes t?! have longitudinally extending metallic strips Til welded to the outer periphery thereof adjacent the space between said adjacent tubes. Strips extend substantially tangentially of tubes 69 and are welded together at 7! so that the tubes and the strips together form a fluidtight baifie. The strips 13 extend from bottom E2 of combustion chamber 3! to a point short of the bottom of the drum 33 thereby forming a space which provides a gas outlet 73 for combustion chamber 3!. Innermost row of tubes 15 of bank 65, which tubes extend along the central paw sage 6i, also has longitudinally extending metallic strips 74 similar to strips l3 welded to the outer periphery of adjacent tubes and extending substantially tangentially of the tubes in the space between adjacent tubes. The strips M are welded together at 15 so that the strips and the tubes together form a fluid-tight baiile between the central passage 61 and the tube bank 65. The strips 14 extend from a point short of the drum to a point short of the drum 35. How of tubes 63 of the tube bank 65 and row of tubes 16 of said bank provide fluid-tight baflies which form a vertically extending gas passage 78 through the tube bank. This passage communicates at the top thereof with the gas outlet '53 and at the bottom thereof with a space 19 adjacent the bottom of the wall as.

The bank 66 of tubes is arranged in a manner similar to the bank (55 having a row of tubes 68 similar to tubes 68 of bank 65, a row of tubes 6.9

similar to the row 69, said tubes 59 having strips Til" extending longitudinally thereof and welded together at 1|, the strips Tll" being arranged in a manner similar to the strips T0 of the bank 65 to form a fluid-tight baflle, while the inner row of tubes of the bank56 has longitudinal strips l4 thereon welded at 15' to form therewith a fluid-tight baliie similar to that formed by the tubes 16 and strips 14 in the bank 65. In this manner, a gas outlet passage 80 is provided for the chamber 32 through which gases flow from said chamber into a vertically extending passage 8| in the tube bank 69. Passage 8| communicates with gas outlet 89 at the top thereofand with space 19 at the bottom. Gas outlet passages 13 and 89, for combustion chambers 3| and 32 respectively, communicate with central passage '61. The space 19 is sealed along drums 35 and 36 by sealing strips 88' and 88" which extend longitudinally of drums 35 and 36 respectively between walls 2H and 43. The sealing strips are mounted in fluid-tight relationship with said drums and Walls and the inner periphery of wall 33.

A bank of horizontally extending superheater tubes 82 is disposed in central passage 51. The superheater tubes 82 are connected at one end thereof to an inlet header 83 which extends substantially vertically in space 46 within dished head 25. superheater inlet header 83 is connected to a dry pipe 92 by a steam conduit 93 is indicated in dot and dash lines in Fig. 4. Tubes 82 extend horizontally through rear wall 4|, the passage 61, and front wall 43, then through a return bend thereafter to pass through wall 43,

passage '51 and wall 42 to an outlet header 84 which extends parallel to and adjacent the inlet header 83. Tubes 82 are, therefore, supported in the front wall 43 and rear wall 4|. i4 is in communication with an outlet conduit 94.

superheater passage 61 communicates at the bottom thereof through a hopper-shaped conduit 85 with the gas outlet conduit (Fig. 1), while the gas space 19, which is in communication with the passages 18 and 8| at the bottom thereof, communicates with combustion gas outlet conduit i5 (Fig. 1).

Clean-out doors 95 and 98 extend through heads and 21 respectively adjacent the space ill at the bottom of the setting l0 so that said space may be cleared of ash particles.

In operation, air under pressure from the air inlet conduit l enters space 88 at the top of the casing 24 through air inlet 48. Some of the air passes to the air chamber 45 and flows therethrough to insulate the casing from the heat of furnace chambers 3| and 32. Other of the air flows into the air spaces 46 and 41 in the heads 26 and 2'5. Burners 49 and 5| receive air from space ll through dampers 5i and 60 respectively which dampers are regulated to admit the proper amount of air.

Gases of combustion in chamber 3| flow in heat exchange relationship with water Wall tubes 63 and tubes 68 and S9 of the tube bank 65 thereafter passing outwardly of chamber 3| through gas outlet l3 over the upper part of the tubes of tube bank 55. Gases flowing through gas outlet 1'3 pass downwardly in the passage 18 into space .9 whence they flow into gas outlet conduit I5. Other of the gases flowing through outlet 13 pass into the superheater passage 61 thence flow downwardly over tubes 82 to enter hopper-shaped conduit whence the gases pass into gas outlet conduit Gases of combustion in the chamber 32 flow in Outlet header 6 heat exchange relationship with the water wall tubes =64 and with tubes 58' and 69' of tube bank 95 thereafter to pass from chamber 32 through gas outlet where the gases flow over the upper part of the tubes of tube bank 66. Gases from passage 80 flow downwardly in gas passage 8| thereafter to enter space 19 at the bottom of casing 24 whence said gases pass into gas outlet con duit l5. Other of the gases from outlet 89 enter superheater passage 61 thereafter to flow downwardly in said passage over the tubes 82 to enter outlet conduits and II.

It will be noted that the gases from both combustion chambers 3| and 32 pass through the superheater passage and through the passage in each of the banks 55 and 66 in parallel at a high rate of speed and with a high pressure drop so that a high rate of heat transfer is obtained. Super-heating of the steam in tubes 82 is controlled by differentially firing furnaces 3| and 32. By controlling the flow of gases of combustion through passage 6! and over superheater tubes 82 through adjusting dampers l1 and I8 superheating of the steam in tubes 92 may also be controlled.

Since the baffles formed by the tubes 69 and strip 10 and tubes 16 and strip 14 are fluid-tight, gases from combustion chamber 3| cannot bypass into the passage 18 or into sperheater passage 61, nor can the gases in passage '51 by-pass into passage 18. Likewise, the gases in chamber 32 cannot by-pass into passage 3| nor can the gases in passage 8| by-pass into superheater passage 61.

Steam temperature is controlled in the vapor generator of the present invention by adjusting dampers I5 and la in gas outlet conduits l5 and I! respectively. In this manner, the relative amount of gas flowing over the superheater and the banks of tubes 55 and '65 may be varied to control the final steam temperature. Also, steam temperature may be controlled. by controlling the firing rate of burners 49 and burners 5| so as to difierentially fire furnaces 3| and 32.

While the invention has been shown and described as used for the generation of steam from water, it will be understood that it is capable of use in generating vapor from liquids in general.

Inasmuch as changes may be made in the form, location and relative arrangement of the several parts of the invention without departing from the principles thereof, it will be understood that the invention is not to be limited excepting by the scope of the appended claims.

What is claimed is:

1. A natural circulation vapor generator comprising a setting having laterally spaced furnaces therein, means for separately firing each furnace, a vapor generating tube group in the space between said furnaces, the tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a passage therebetween, a superheater in the passage, an upper vapor and liquid drum in the setting communicating with the upper ends of the tubes of said group, spaced lower drums in the setting, said drums respectively being in communication with the lower ends of the tubes of said tube banks, baffie means separating the passage from each of said banks, other bafile means associated with each of said banks and positioned in spaced relationship with said first-mentioned baffle, said baflie and other bafiie thereby forming a gas outlet flow path through the banks, the furnaces each having a gas opening in communica- 1.- tion' with the-*gasgoutlet-flow path oiatube bank and: with the passage between said banks, the passage between the banksandthe gas; outlet flow paths havingseperate gas outlets located to respectively receive gasesafter said gases have passed through said passage and through said flow paths, and means for separately controlling the flow of gases through said passage and the flow of gases through said gas'outlet'flow paths.

2. A naturalcirculation vapor generator comprising asetting having laterally spaced furnaces therein, means for separately firing each furnace, a generally vertically extending vapor generating tube group in, the space between said furnaces, the tube group comprising a plurality, of spaced tubes arranged inlaterally. adjacent tube banks spacediroin one another to provide a vertically extending passage therebetween, a superheater comprising, a plurality of horizontally extending tubes disposed in the passage, an upper vapor and liquid drum in the setting communicating-with the upper ends of the tubes of said group, spaced lower drums in the setting located on opposite sides of said passage, said drums respectively being in communication with the lower ends'of the-tubes'of said tube banks, bailie incansseparating the passage from each of said banks,'other baflle means associated with each of said banks and: positioned" in spaced relationship with said first-mentioned baffle, saidbaille'and other baille thereby forming a gas outlet flow path through the banks, the furnaceseach having a gas opening in communication with the gas outlet flow path of a tube bank and with the passage between said banks, the passagebetween the banks and the gas outlet fiow paths having separate gas outlets located to respectively receive after said: gases have passed through said pas and through said iicw paths, and means for separately controlling the flow of gases through said passage and the flow of gases through said gas outlet flow paths.

3. A; natural circulation vapor generator comprising a setting having'laterally spaced furnaces therein, means for separately firing each furnace, a vapor generating tube group in the space between said furnaces, the tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a passage-therebetween, a superheater in the passage, an upper vapor and liquid drum in the setting communicating with the upper ends of the tubes of said group, spaced lower drums in the setting, said drums respectively being in communication with the lower ends-oi the tubes of said tube banks, baffle means separating the passage from each of said banks, other bafiie means associated. with each of said banks and positioned in spacedrelationship with said firstmentioned each baiiie and other. baifie. comprising a plurality of tubes. of a bank laterally spaced from one another in a row extending longitudinally of said druin, the baffles also com prising elongated, fiat, metallic strips having opposite sides and longitudinally, extending opposite edges, said strips being secured to adjacent tubes to extend longitudinally thereof with a portion of one side of the strips abutting a tube and with the opposite side of the strips closely adjacent the opposite side oi another strip. on an adjacent tube in therow, the space betweensaid tubes and the thickness of said strip and said other strip being. substantially equal, the strips extending in said spacessubstantially at a rightangle tosaid passage andwith a longitudinal edge &

h oi' i t aid-passage, mange cur n dja tr scze h rr n; a flu dht: ma er along one; longitudinal edge thereof, said;bafi le and other baiiie therebyfo-rminga gas outletfiow paththrough the banks, thefurnaces each having a gas opening in communication with the gasoutlet flow path of a tube bank. and: with the passage between said banks, the passagebetween the banks and the gas outlet flow paths having separate as outlets located to respectively receive gasesgafter-said gases have passed through said passage and through said flow paths. and means for'separately controlling theflow of gases through saidpassage and the flowot gases through said gas outlet flow, paths.

4. A natural circulation vapor generator comprising a setting having a generally vertically extending vapor generating tube group therein, said tube; loup; comprising aplurality of spaced tubes arranged in, laterally adjacent tubebanks spaced from oneanother-to provide a vertically extending substantially centrally located. passage therebetween, a superheater in the passage, an upper vapor and liquid drum-in the setting above said passage and in substantial vertical align:- rnenttherewith, the upper ends of' the tubesof said; groupccmrnunicating with the drum, spaced lower drumsin the setting on opposite; sides of said; passage, the drumsrespectively being in communication with the lower-ends of the tubes of a t be banks, a, furn e at lv ad ac n each of said tube banks, means for firing; each furnace, bafilc means separating; the passage from eachofsaid banks; other baffle means asso: ciated; with each of said; banks and positioned in spaced relationship with said firstementioned baiile, said baillc and other bathe thereby forming a gas outlet, flow path through banks, the furnaces each havinga gasopeningv in communi: cation with the gasoutlet flow path of the tube bank adjacent said furnace andwith the passage between said, banks, gas outlet, means. forming a gas outlet forsaidgas outlet flow. pathsthrough the banks, other gas outlet means forming a gas outlet, separate'fromsaid gas outlet means and providing a gas outlet for said passage, said gas outlet means; and other gas outlet means being located, to receive gases after said gases have passed through said, passage and gas outlet flow paths, and means for separately controlling the flow, of gases through said: passage and'the now of gasesthrough said gas outlet flow paths.

5. Anatural circulationvapor generator having asetting comprising a cylindrically-shaped, fluid tight casing, an air compressor, conduit means for conductingair under pressure intothe casing, a, generally. vertically extending vapor generating tube group in the central part of said casing, said tube groupcomprising a plurality of spaccd tubes arranged in laterally adjacent tube banks spaced from one another to provide a vertically extendingl substantiallycentrally located passage therebetween, asuperheater in the passage, an upper vapor and liquid drum disposed in the setting and. communicating with the upper ends of the tubes of said group, said drum being so disposed that the longitudinal axis thereof extendsin sub stantiallythe same vertical ,lane as the longitudinal of the setting, spaced lower drums in the setting located on opposite sides of said passage with the longitudinal axes thereof extending in horizontal planes parallel to the horizontal axes of said upper drum and said setting, said drums respectiv ly being in communication with the lowerends of the tubes of said tube banks, a furnace laterally adjacent each of said tube banks, said chambers being in communication with the air compressor to receive air under pressure therefrom for combustion, means for firing each furnace, baflle means separating the passage from each of said banks, other bafile means associated with each of said banks and positioned in spaced relationship with said firstmentioned bafile, said baffle and other bafile thereby forming a gas outlet flow path through the banks, the furnaces each having a gas opening in communication with the gas outlet flow path of the tube bank adjacent said furnace and with the passage between said banks at one end of said flow path and passage, gas outlet means forming a gas outlet for said gas outlet flow paths through the banks, other gas outlet means forming a gas outlet separate from said gas outlet means and providing a gas outlet for said passage, said gas outlet means and other gas outlet means being located at the end of said flow paths and passage opposite said one end to receive gases after said gases have passed through said passage and gas outlet fiow paths, and means for separately controlling the flow of gases through said passage and the flow of gases through said gas outlet flow paths.

6. A vapor generator having a setting comprising a cylindrically-shaped fluid-tight casing, an air compressor, conduit means for conducting air under pressure into the casing, a generally vertically extending vapor generating tube group in the central part of said casing, said tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a vertically extending passage, a superheater in the passage, an upper vapor and liquid drum disposed in the setting and communicating with the upper ends of the tubes of said group, said drum being so disposed that the longitudinal axis thereof extends in substantially the same vertical plane as the longitudinal axis of the setting, spaced lower drums in the setting located on opposite sides of said passage with the longitudinal axes thereof extending in horizontal planes parallel to the horizontal axes of said upper drum and said setting, said drums respectively being in communication with the lower ends or the tubes of said tube banks, a furnace laterally adjacent each of said tube banks, said chambers being in communication with the air compressor to receive air under pressure therefrom for combustion, means for firing each furnace, a wall extending around and spaced from the inner periphery of the casing from a point adjacent said upper drum at one side thereof to a point adjacent the upper drum at the opposite side thereof, said space between the wall and the casing being adapted to receive air under pressure from the interior of the setting, baffle means separating the passage from each of said ban-ks, other baffle means associated with each of said banks and positioned in spaced relationship with said first-mentioned bafiie, said bafile and other baille thereby forming a gas outlet flow path through the banks, the furnaces each having a gas opening in communication with the gas outlet flow path of the tube bank adjacent said furnace and with the passage between said banks at one end of said flow path and passage, gas outlet means forming a gas outlet for said gas outlet flow paths through the banks, other gas outlet means forming a gas outlet separate from said gas outlet means and providing a gas outlet for said passage, said gas outlet means and other gas outlet means being located at the end of said flow paths and passage opposite said one end to receive gases after said gases have passed through said passage and gas outlet flow paths, and means for separately controlling the flow of gases through said passage and the flow of gases through said gas outlet flow paths.

7. A vapor generator having a setting comprising a cylindrically-shaped fluid-tight casing, an air compressor, conduit means for conducting air under pressure into the casing, a generally .vertically extending vapor generating tube group in the central part of said casing, said tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a vertically extending passage, a superheater in the passage, an upper vapor and liquid drum disposed in the setting and communicating with the upper ends of the tubes of said group, said drum being so disposed that the longitudinal axis thereof extends in substantially the same vertical plane as the longitudinal axis of the setting, spaced lower drums in the setting located on opposite sides of said passage with the longitudinal axes thereof extending in horizontal planes parallel to the horizontal axes of said upper drum and said setting, said drums respectively being in communication with the lower ends of the tubes of said tube banks, a furnace laterally adjacent each of said tube banks, said chambers being in communication with the air compressor to receive air under pressure therefrom for combustion, means for firing each furnace, baffle means separating the passage from each of said banks, other baffle means associated with each of said banks and positioned in spaced relationship with said first-mentioned bafile, said bafiie and other baffle thereby forming a gas outlet flow path through the banks, the furnaces each having a gas opening in communication with the gas outlet flow path or" the tube bank adjacent said furnace and with the passage between said banks at one end of said flow path and passage, gas outlet means forming a gas outlet for said gas outlet flow paths through the banks, other as outlet means forming a gas outlet separate from said gas outlet means and providing a gas outlet for said passage, said gas outlet means and other gas outlet means being located at the end of said how paths and passage opposite said one end to receive gases after said gases have passed through said passage and gas outlet flow paths, means for separately controlling the flow of gases through said passage and the flow of gases through said gas outlet flow paths, and a gas turbine associated with said air compressor, said gas turbine and said other gas outlets being in communication so that the gas turbine is actuated by gases of combustion from the vapor generator.

8. A vapor generator comprising a setting having a generally vertically extending vapor generating tube group therein, said tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a vertically extending passage therebetween, a superheater in the passage, an upper vapor and liquid drum in the setting above said passage and in substantial vertical alignment therewith, the upper ends of the tubes of said group communicating with the drum, spaced lower drums in the setting on opposite sides of said passage, the drums respectively being in communication with the lower ends of the tubes of said tube banks, a furnace laterally adjacent 11 eachof saidtube banks, means for firing each "furnace,"baffle means separating thepassage from "each of said banks,.other bafile means associated with ea'ch of said banks and positioned inspaced i'relationship with said first-mentioned baflle, each -baIffle'and other baffle comprising arplurality of tubes of abank laterally spaced from one another -ln'a'row extendinglongitudinally of said drum, ithebafiles also comprising elongated, flat, metal- :lic strips having opposite sides and longitudi- -nally-extending opposite edges, said strips being secured to adjacent tubes to extend longitudinally thereof with a portion of one side of the strips abutting a tube and with the opposite side of tlresstripsclosely adjacent the opposite side of another strip on an adjacent tube in the row, the space between said-tubes and the thickness of said strip and said other strip being substantially eduaL-the strips extending in said spaces substantially *at a right-angle to said passage and with-a lo'ngitudinal edge thereof adjacent :said q'aassa-ge, means for securing adjacent strips to- :gether in a fluid-tight manner along one l'ongi- 'tudinal edge thereof, said bar-lie and other'lnafile thereby forming a gas outlet fiow path through the banks, thefurnac'es each having a .gas opening in communication with the outlet .flow pathbf'thetube bank adjacent said furnace and with-the passage'between said banks, gas outlet means'forrning aigas outlet for said outlet iiow paths'through the banks; other gas outlet means-forming au as outlet separate from said gas outletmeans andrproviding a gas outlet for said passage, said gas outlet means and other gas outlet-means being located to receive gases after said-gases have passed through said passage and gas outlet flow paths, and means for separately controllin the flow of gases through said passage and the flow of gases through said gas out- 'let fiow paths 9. vaporgenerator comprising a setting having-agenerally vertically extending vapor gen- 'eratingtubegroup therein, said tube group cornqnisinga plurality of spaced tubes-arranged in ,laterally' adjacent tube banks spaced from one another-to provide a vertically extending-passage therebetween, asuperheater in the passage, an upper vaponand liquid drum in the settingabove said 'pas's'age in substantial vertical align- 'ment therewith, the upper ends of the'tubes of 'sa 'id group communicating with the drum,spaced l'o'wer drums in-the setting onoppositesides of said passage, the drums respectively being in cominunication with the lower ends of the tubes of 'saidl-tube banks, a furnace laterally-adj acent each of-said tube banksyzneans for firing each turnace, .baiile means separating the passage from each of said banks, other baffle means associated with each .ofsaid :banks' and positioned in spaced relationship with said first-mentioned baille,'each bafile and other bafile comprising a plurality of tubes-of a bank laterally spaced from one another in a row extending longitudinally of said drum, the baffles also comprising elongated, fiat, metallic strips having opposite sides and longi- *tudinally extending opposite edges, said strips'being secured by welding along'one of said longitudinal'edges to the tube adjacent thereto to ex- -tend=longitudinally thereof with a portion ofone 'side of the strips abutting a tube and with the opposite side of the strips closely adjacent the opposite side of another strip on an adjacent tube in therow, the -spacebetween said tubes and the thickness of said strip and said other strip being substantially e'qual,-the strips: extending in said spaces substantially at a right angle .to said passage and with a longitudinal edge thereof =adjacent said passage, a weld securing adjacent strips together in a fluid-tight manner along :one longitudinal edge thereof, said baiile and other bailie thereby forming a gas outlet flow path through the banks, the furnaces veach having a gas opening in communication with the gas outlet flow path of the tube bank adjacent said furnace and with the passage between'saidbanlzs,

gas outlet means forming a gas outlet for said gas outlet flow paths through the'banks, other gas outlet means forming a gas outlet separate from said gas outlet means and providing'a-gas outlet for saidpassage, said gasoutletmeansand other gas outlet means being located to receive gases after said gases have passed through said passage and gas outlet flow paths, and 'means for separately controlling-the how of gases through saidlpassage and the flow-of gases through said gas outlet flow paths.

10. A vapor generator having a setting ;comprising a cylindrically shaped fluid-tight casing, an'air compressor, conduit means for :con'ducting air underpressure into the casing, a generally vertically extending vapor generating tube group in the central part of said casing, :zsaid tubegroup comprising apluralityof spaced tubes arranged in laterally adjacent tube banks-spaced from one another to provide a verticallytextending passage, a superheater in the passage, :an upper vapor and liquid drum disposed in :the setting and connnunicating with the upper ends of the tubes of said group, said: drum .beingiso disposed that the longitudinal axis thereo'fcxtends in substantially the same vertical plane as the longitudinal axis of the setting, :spaced lower drums in the setting located 'onopposite sides of said passage with the longitudinalaxes thereof extending in horizontal planes parallelto the horizontal axes of said upper drum. and said setting, said drums respectively being in communication with the lower :ends of the tubes of said tube banks, a furnace laterally adjacentzeach of said tube banks, said chambers'being in communication with the air compressor to receive air under pressure therefrom for combustion, means for firing each furnace, baflle means-separating the passage from each of said banks other baffie'rneans associated witheach of said @banks and positioned in spaced relationship With;-'said first-mentioned baffle, each bafile. and:other baffle comprising a vplurality of tubes of a shank laterall spaced from one another in .arowrextending longitudinally of said drum, the baffles also comprising elongated, flat, metallicstrips :having opposite sides and longitudinally extending opposite edges, saidstrips being secureduto adjacent tubes to extend longitudinally thereof with a portion of one side of the strips abutting a'tube and with the opposite side :of the strips closely adjacent the opposite side of another strip on an adjacent tube in the row,..the space'sbetween said tubes and the thicknessof said strip and said other strip being substantially equal, .the strips extending in said spaces substantially at a right angle to said'passage and with allongitu- 'dinal edge thereof adjacent said passage'means forsecuring adjacent strips togetherv in aifiuidtight manner along one longitudinal edge thereof, said bafile andother baflle thereby donning-a gas outlet flow path through thebanks, the furnaces each-having a gas opening in communication with' the gas outlet fl0w pathbf-the'tube bank adjacent said-furnace-and=wlththepassage between said banks at one end of said flow path and passage, gas outlet means forming a gas outlet for said gas outlet flow paths through the banks, other gas outlet means forming a gas outlet separate from said gas outlet means and providing a gas outlet for said passage, said gas outlet means and other gas outlet means being located at the end of said flow paths and passage opposite said one end to receive gases after said gases have passed through said passage and gas outlet flow paths, means for separately controlling the flow of gases through said passage and the flow of gases through said gas outlet flow paths, and a gas turbine associated with said air compressor, said gas turbine and said other gas outlets being in communication so that the gas turbine is actuated by gases of combustion from the vapor generator.

11. A vapor generator having a setting comprising a cylindrically shaped fluid-tight casing, an air compressor, conduit means for conducting air under pressure into the casing, a generally vertically extending vapor generating tube group in the central part of said casing, said tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a vertically extending passage, a superheater in the passage, an upper vapor and liquid drum disposed in the setting and communicating with the upper ends of the tubes of said group, said drum being so disposed that the longitudinal axis thereof extends in substantially the same vertical plane as the longitudinal axis of the setting, spaced lower drums in the setting located on opposite sides of said passage with the longitudinal axes thereof extending in horizontal planes parallel to the horizontal axes of said upper drum and said setting, said drums respectively being in communication with the lower ends of the tubes of said tube banks, a furnace laterally adjacent each of said tube banks, said chambers being in communication with the air compressor to receive air under pressure therefrom for combustion, means for firing each furnace, a wall extending around and spaced from the inner periphery of the casing from a point adjacent said upper drum at one side thereof to a point adjacent the upper drum at the opposite side thereof, said space between the wall and the casing being adapted to receive air under pressure from the interior of the setting, baffle means separating the passage from each of said banks, other baffle means associated with each of said banks and positioned in spaced relationship with said first-mentioned baflle, said bafile and other bafile thereby forming a gas outlet flow path through the banks, the furnaces each having a gas opening in communication with the gas outlet flow path of the tube bank adjacent said furnace and with the passage between said banks at one end of said fiow path and passage, gas outlet means forming a gas outlet for said gas outlet flow paths through the banks, other gas outlet means forming a gas outlet separate from said gas outlet means and providing a gas outlet for said passage, said gas outlet means and other gas outlet means being located at the end of said flow paths and passage opposite said one end to receive gases after said gases have passed through said passage and gas outlet flow paths, means for separately controlling the flow of gases through said passage and the flow of gases through said gas outlet flow paths, and a gas turbine associated with said air compressor, said gas turbine and said other gas outlets being in communica- 14 tion so that the gas turbine is actuated by gases of combustion from the vapor generator.

12. A vapor generator having a setting comprising a cylindrically shaped fluid-tight casing, an air compressor, conduit means for conducting air under pressure into the casing, a generally vertically extending vapor generating tube group in the central part of said casing, said tube group comprising a plurality of spaced tubes arranged in laterally adjacent tube banks spaced from one another to provide a vertically extending passage, a superheater in the passage, an upper vapor and liquid drum disposed in the setting and communicating with the upper ends of the tubes of said group, said drum being so disposed that the longitudinal axis thereof extends in substantially the same vertical plane as the longitudinal axis of the setting, spaced lower drums in the setting located on opposite sides of said passage with the longitudinal axes thereof extending in horizontal planes parallel to the horizontal axes of said upper drum and said setting, said drums respectively being in communication with the lower ends of the tubes of said tube banks, a furnace laterally adjacent each of said tube banks, said chambers being in commmunication with the air compressor to receive air under pressure therefrom for combustion, means for firing each furnace, a wall extending around and spaced from the inner periphery of the casing from a point adjacent said upper drum at one side thereof to a point adjacent the upper drum at the opposite side thereof, said space between the wall and the casing being adapted to receive air under pressure from the interior of the setting, baflle means separating the passage from each of said banks, other baiiie means associated with each of said banks and positioned in spaced relationship with said first-mentioned baflie, each baffie and other baffle comprising a plurality of tubes of a bank laterally spaced from one another in a row extending longitudinally of said drum, the baffles also comprising elongated, flat, metallic strips having opposite sides and longitudinally extending opposite edges, said strips being secured to adjacent tubes to extend longitudinally thereof with a portion of one side of the strips abutting a tube and with the opposite side of the strips closely adjacent the opposite side of another strip on an adjacent tube in the row, the space between said tubes and the thickness of said strip and said other strip being substantially equal, the strips extending in said spaces substantially at a right angle to said passage and with a longitudinal edge thereof adjacent said passage, means for securing adjacent strips together in a fluidtight manner along one longitudinal edge thereof, said baffle and other baffle thereby forming a gas outlet flow path through the banks, the furnaces each having a gas opening in communication with the gas outlet flow path of the tube bank adjacent said furnace and with the. passage between said banks at one end of said flow path and passage, gas outlet means forming a gas outlet for said gas outlet flow paths through the banks, other gas outlet means forming a gas outlet separate from said gas outlet means and providing a gas outlet for said passage, said gas outlet means and other gas outlet means being located at the end of said flow paths and passage opposite said one end to receive gases after said gases have passed through said passage and gas outlet flow paths, means for separately controlling the flow of gases through said passage and the flow of gases through said outlet flow paths, 

